Yes Magic can and does ride bridleless. She is featured in many of his training videos, including some of the freestyle training videos where she is working on serpentines bridleless. I agree she looks very tight in this video and she's wearing a curb bit and Pat is using a lot of bit contact. He is not however using any MORE bit contact than any other big name trainer or competitor. He is not jerking on her face or yanking her head around. Have you watched the Road to the Horse videos of Clinton Anderson? He is literally damn near tearing the colt's bottom jaw off in the 2011 RTTH. I thought if he yanked and jerked any harder, thge reins would tear right off the bit.
Dressage horses usually have froth slobbering down their front legs and chests because of so much contact they can't even swallow. But that's considered "beautiful" and the foam is considered a "good thing." (I think it's horrible.)
I couldn't begin to say why Magic is requiring a curb bit and that much contact in that video. What I do know about her is that she was a very damaged, complicated, ruined horse that Pat essentially rescued. She had been through many trainers, was deemed unrideable and dangerous. The fact that Pat does everything he does with her is absolutely amazing, in my opinion.